Rotary machine support



Dec. 15, 1964 F. J. BEI'N'E 3,161,389

ROTARY MACHINE SUPPORT Filed. June 19, 1962 "steam turbine, it is support arm could take place.

3,161,389 ROTARY MACHINE SUPPORT Floyd J. Beine, Greendale, Wis, assignor to Allis- Chalmers Manufacturing Company, Milwaukee, Wis. Filed Eune 19, 1962, Ser. No. 203,530 4 Claims. (Cl. 248-14) This invention pertains to a support structure and more particularly to a support structure for large rotating machinery such as steam turbines or the like.

When supporting a large rotating machine such as a quite frequently the practice to provide the machine with a support arm rigidly connected to the turbine casing and laterally extending therefrom. This support arm, or a number of such arms, rests on a pedestal to support the weight of the turbine.

Since considerable changes in dimensions of the turbine occur between the low shutdown temperature and high operating temperature, it is necessary to provide a sup-port which will accommodate these dimensional changes. One type of support includes a half ball or half sphere that contacts the under side of the support arm on a slide plate and which rests in a socket attached to the pedestal. With such an arrangement, the ball is permitted to move in the socket support to insure uniform low bearing pressure which prevents galling between the top of the half ball and slide plate when thermal expansion occurs in theturbine casing moving the support arm over the half ball.

While the turbine is shut down, such a support structure is sufficient to support the turbine. However, when the turbine is rotating, a moment is set up which attempts to lift the support arm off the half ball on one side of the turbine. To overcome this rotational moment, it is common practice to clamp the support arm to the pedestal by means of a plate positioned above the support arm and connected to the pedestal. However, since the support arm is attached to the turbine, its temperature will rise more than the temperature of the clamp and it will, therefore, expand more than the clamp. It is, therefore, necessary to provide a large clearance between the clamp plate and the support arm so that after the support arm has expanded there is not excessive binding between the clamp and the support arm which would produce galling between the half ball and the support arm slide plate.

Prior to applicants invention, it was therefore necessary to provide sufficient clearance between the support arm and the. clamp plate so that this expansion of the However, as the turbines became larger and the rotational moments more nearly equaled the weight moments the turbine would have a greater tendency to flutter at its sup-port arm because of this clearance and cause internal rubbing between the shaft and seals.

It is applicants intention and the general object of this invention to provide a support structure of the hereinbefore described typewherein the previously required large cold clearance between the support arm and the clamp plate is no longer necessary.

Another object of the subject invention is to provide a support structure of the hereinbefore described type wherein no cold clearance is required between the support arm and the clamp plate.

A further object of the subject invention is to provide a support structure of the hereinbefore described type wherein the area of contact between the support arm and the clamp plate is substantially less than the surface area of the clamp plate and is strategically located to facilitate smaller clearances.

An additional object of the subject invention is to pro United States laterit C complementary socket 18 vide a support structure of the hereinbefore described type wherein a resilient means such as a spring is provided between the support arm and the clamp plate to permit relative thermal expansion between the arm and the clamp.

A further object of the subject invention is to provide a support structure of the hereinbefore described type wherein a resilient means is provided between the support arm and the clamp plate and wherein the area of the spring which contacts the plate is substantially less than the surface area of the clamp plate.

These and other objects of the invention will become more fully apparent as the following in light of the accompanying drawing, wherein:

FIG. 1 is a top view of the support structure constructed in accordance with the invention;

FIG. 2 is a sectional view taken along the of FIG. 1;

FIG. 3 is a sectional view taken along the lines ill-III of FIG. 2; and

FIG. 4 is an enlarged view of a particular type of resilient means which may be provided between the clamp plate and support arm.

Referring to the drawing, a rotating machine generally designated 11 is shown provided with a support arm 12 rigidly attached thereto in any conventional manner and lines IIII the rotating machine 11 on a pedestal or supporting surface generally designated 13. plate 17 may be connected to the under side of the support arm 12 in any conventional manner such as by screws 16 passing through it. A half ball 14 rests in a which may be connected to a bedplate 19 in any conventional manner such as by cap screws 21. The bedplate 19 may be connected to the pedestal in any conventional manner dictated by the particular application of the subject invention. With such an arrangement relative movement between the turbine and pedestal due to differential thermal expansion may be accommodated.

As so far described, the ported on the pedestal 13 in the socket 18.

to rotate, a moment is set up which attempts to lift the sup-port arm 12 and slide plate 17 from the half ball 14. It is, therefore, necessary to clamp the support arm to the pedestal. This clamping connection may be effected in any conventional manner and is herein shown as including a clamp plate 22 disposed in overlying relation to the support arm 12 and connected to the bedplate 19 in any conventional manner such as by elongated cap screws 23. Spacers 24 and 26 may also be provided between the bedplate 19 and the lower surface of the clamp plate 22.

To carry out the intent of the invention the contact between the support arm 12 and clamp plate 22 is through a boss or contact means 27 having a contacting surface area which is considerably less than the surface area 28 of the clamp plate 22 and preferably located directly over the center line of the half ball allowing considerable deflection of the support arm during changing loads without afiecting the clearance between the boss 27 and clamp plate 22. The boss 27 is also preferably equally spaced between the cap screws 23. With this arrangement, the lifting force of the support arm 12, due to the rotational moment of the machine, acting against the clamp plate 22 is concentrated at the point were the boss 27 contacts the clamp plate surface 28. This results in the clamp plate 22 acting as a spring which permits some binding contact between the support arm and clamp plate without exerting excessive force on the description is read To this end, a slide half ball 14 to cause scoring of the half ball and the slide plate 17. Without the relatively small contacting surface of the boss 27 located above the half ball center line and near center span of the clamp plate, the clamp plate would act snbstantially as a rigid member and would, therefore, necessitate m large spacing between the clamp plate and support to permit thermal ex.- pansion and deflection of the support arm so as not to cause an excessive force to exist between the half ball and the socket atter the support arm has expanded due to a temperature increase' 3 i i i In the preferred embodiment, applicant has also provided a disk spring 29 between the clamp plate and support arm. In this preferredembodiment, the boss '27 is a part of the disk spring 29. The spring'29 ofiers considerably less resistanceto movement of the support arm 12 than does the spring action of the clamp plate 22.

As shown in the drawing, the elements of applicants invention are in the condition they assume when the machine is at a standstill, As the machine begins to rotate, and before it has heated to'its' normal running temperature, any tendency of the support arm 12 to lift from the half ball 14 is resisted by the disk spring 29. The disk spring, therefore, resists any tendency of the sup ort arm to flutter thereby protecting the mating surfaces of the half ball 14 and the slide plate 17 from being damaged by the half ball pounding against the slide plate and also preventing any internal rubbing or wiping damage between the shaft and seals. As the temperature of the support arm increases, the disk spring 29 is easily compressed until the disk spring is bottomed out against the support arm, thereafter causing the disk spring to act as a rigid member. A space 31 provided between legs 32 of the disk spring is less than the space 33 provided between the upper portion of the disk sprin and the lower surface of the clamp plate to insure that the only contact between the support arm 12 and the clamp plate 22 is through the boss 27. Furthermore, the lim t f mpre sion of th di k sp 2 w i h .is dictated by the space 31 is designed to substantially cornpensate for the expansion of the support arm' 12,as it is h t d om thelccld cond t o t t max mum t mperature. However, inthe eventthat'further expansion does occur the clamp plate 22 does provide additional spring action because of the relatively small contacting area and location of the boss 2 i W this r me t app c t has provid d an e and inexpensive support structure for large rotating niachines wherein the thermal expansion clearance necessary between the machine and the clamp plate is not nearly as critical and is greatly reduced that which was pr o s y eq i edfurth mq e by employ n a disk spri g between'th upport rm and clamp pla any flutter that might exist before the machine has reached its operating temperature has been overcome,

Although only one embodiment of the present invention has been illustrated and described, it will be apparent to those skilled in the art that various changes and modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims.

Having now particularly described and ascertained the nature of my said invention and the manner in which it is to be performed, I declare that what I claim is:

1. A support structure for attaching a machine to a supporting surface comprising: a support arm rigidly connected to said machine; a clamp plate; spaced means on opposite sides of said support arm securing said clampplate to said support surface in overlying relation to 'said support arm; and resilient means positioned between and contacting both said support arm and said clamp plate, the surface area' of said resilient means contacting said clamp plate'being less than the surface area of said support arm between said securing means and spaced from said securing means to enable said clamp plate to act as a resilient member when said resilient means has been completely compressed.

2. The support structure set forth in claim 1 wherein the surface of said resilient'rneans contacting said support arm is substantially equally spaced from said securing means.

3. A support structure for attaching an elastic fluid turbine orlike machine subject to high operating temperature toa supporting surface comprising: a support arm rigidly connected to said "machine; a clamp plate positioned above and having portions extending to either side of said support arm; means attached to the extending portions of said clamp plate securing said clamp plate to said supporting surface a predetermined distance above said support arm'when said machine is shut down to permit thermal expansion of said support arm while said machine temperature'increases to said high p ati empe u and esil en c mp on m s p i n t e so c nta t b ween a p r m d said c amp plate h in a clamp p t Contacting r c a ea le' sth n th facear a' of Said s ppo a be tween said securing means, the compressible limit of said res ien mean b in re ched be e s s pp rt m contacts said clamp plate.

.4. The support structure set forth in claim 3 wherein the center of the area of contact between said resilient compression means and said clamp plate is substantially equ d sta t't m said cu i g mean References Cited in the file of this patent UNITED STATES PATENTS Gerosa Apr. 23, 1918 1,947,489 Nold Feb. 20, 1934 2,056,733 Neale Oct..6, 1936 2,195,873 Lord Apr. 2, 1940 3,003,466 'Matarazzo Oct. 10, 1961 

1. A SUPPORT STRUCTURE FOR ATTACHING A MACHINE TO A SUPPORTING SURFACE COMPRISING: A SUPPORT ARM RIGIDLY CONNECTED TO SAID MACHINE: A CLAMP PLATE; SPACED MEANS ON OPPOSITE SIDES OF SAID SUPPORT ARM SECURING SAID CLAMP PLATE TO SAID SUPPORT SURFACE IN OVERLYING RELATION TO SAID SUPPORT ARM; AND RESILIENT MEANS POSITIONED BETWEEN AND CONTACTING BOTH SAID SUPPORT ARM AND SAID CLAMP PLATE, THE SURFACE AREA OF SAID RESILIENT MEANS CONTACTING SAID CLAMP PLATE BEING LESS THAN THE SURFACE AREA OF SAID SUPPORT ARM BETWEEN SAID SECURING MEANS AND SPACED FROM SAID SECURING MEANS TO ENABLE SAID CLAMP PLATE TO ACT AS A RESILIENT MEMBER WHEN SAID RESILIENT MEANS HAS BEEN COMPLETELY COMPRESSED. 